Forms processing: Forms identification and recognition

In This Topic

Form identification - is a process that compares the form image with one or more images of form templates and determines the form template that matches the form. During the identification SDK calculates the transformation matrix that defines the translation, rotation and scale of form relative to the form template. Also during the identification SDK determines the confidence to the results of form recognition.

The SDK would identify a form, even if image of form is rotated or scaled comparing to the form template. The SDK would NOT identify the form, if image of form is dimensionally distorted or warped comparing to the form template.

Form recognition - is a process of reading data from form fields. During the form recognition SDK creates a list of recognized form fields. For each recognized field SDK returns the field value and confidence to the recognition result.

FormRecognitionManager class is intended for identification and recognition of form. The process of identification and recognition can be performed for a single form or for several forms at once, that process can be synchronous or asynchronous. The class can provide information about progress of recognition. Also class allows to apply the processing commands to the template form image and filled form image before form identification.

For synchronous recognition of form is necessary to use FormRecognitionManager.Recognize method, for asynchronous recognition of form is necessary to use FormRecognitionManager.RecognizeAsync method.

The result of recognition is returned as an instance of FormRecognitionResult class. The class FormRecognitionResult contains the result of form identification - FormRecognitionResult.TemplateMatchingResult, and the result of form recognition - FormRecognitionResult.RecognizedPage.

A form field is represented by FormField class, which determines the field name, field value and confidence to the result of form recognition. Also class FormField contains reference to a template of form field. Here is a list of standard classes, which define form fields:

FormField - a base class for any form field
- OmrField - a form field, which defines an abstract optical mark
  - OmrEllipticalField - a form field, which defines an optical mark bounded by ellipse
  - OmrRectangularField - a form field, which defines an optical mark bounded by rectangle
  - OmrFieldTable - a table, which table cell is an optical mark field
- OcrField - a form field, which defines a text
- FormFieldGroup - a group of form fields
  - FormFieldTable - a table of form fields

Architecture of FormField class is open, so user may define its own custom form fields if necessary. Forms Processing Demo application contains an example of form field that defines a barcode.

Identify and recognize a document that contains only one form

For identification and recognition of document that contains only one form is necessary to do the following:

Identify the template of document form
Perform the form recognition

Here is an example that demonstrates how to identify and recognize a form synchronously.

VB.NET

' The project, which uses this code, must have references to the following assemblies:
' - Vintasoft.Imaging
' - Vintasoft.Imaging.FormsProcessing

''' <summary>
''' Recognizes single image synchronously.
''' </summary>
''' <param name="templateManager">The template manager.</param>
''' <param name="image">The image.</param>
Public Shared Sub RecognizeSingleImageSync(templateManager As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormTemplateManager, image As Vintasoft.Imaging.VintasoftImage)
    ' create template matching command
    Dim templateMatching As New Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand()
    ' set minimal confidence
    templateMatching.MinConfidence = 0.6F
    ' set template images
    templateMatching.TemplateImages = templateManager.TemplateImages
    ' create recognition manager
    Dim recognitionManager As New Vintasoft.Imaging.FormsProcessing.FormRecognitionManager(templateMatching, templateManager)

    ' if your form template contains OCR fields,
    ' make sure OCR engine manager is initialized before recognition
    ' (otherwise recognition will return null (Nothing)),
    ' see OCR field recognition examples

    ' subscribe to ImageRecognitionError event to output recognition errors
    AddHandler recognitionManager.ImageRecognitionError, AddressOf recognitionManager_ImageRecognitionError

    ' recognize the image
    Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = recognitionManager.Recognize(image)

    ' unsubscribe from ImageRecognitionError event
    RemoveHandler recognitionManager.ImageRecognitionError, AddressOf recognitionManager_ImageRecognitionError

    ' if recognition failed with error (see ImageRecognitionError event handler output)
    If recognitionResult Is Nothing Then
        Return
    End If

    ' get the result of image comparison
    Dim imageCompareResult As Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult = recognitionResult.TemplateMatchingResult.ImageCompareResult
    ' if result is not reliable
    If Not imageCompareResult.IsReliable Then
        ' matching template is not found
        System.Console.WriteLine("Matching template is not found.")
    Else
        ' get recognized page
        Dim recognizedPage As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage = recognitionResult.RecognizedPage
        ' write page info
        System.Console.WriteLine(String.Format("Matching template: {0}; confidence: {1:F1}%.", recognizedPage.Name, imageCompareResult.Confidence * 100))

        ' get form field count
        If recognizedPage.Items.Count = 0 Then
            System.Console.WriteLine("No form fields were recognized.")
        Else
            System.Console.WriteLine(String.Format("Recognized form field count: {0}", recognizedPage.Items.Count))
            ' for each recognized form field
            For Each recognizedField As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField In recognizedPage.Items
                ' write field info
                System.Console.WriteLine(String.Format("  Name: {0}; value: {1}; confidence: {2:F1}%", recognizedField.Name, recognizedField.Value, recognizedField.Confidence * 100))
            Next
        End If
    End If
End Sub

''' <summary>
''' Handles the ImageRecognitionError event of the FormRecognitionManager.
''' </summary>
Private Shared Sub recognitionManager_ImageRecognitionError(sender As Object, e As Vintasoft.Imaging.FormsProcessing.FormRecognitionErrorEventArgs)
    System.Console.WriteLine(e.Exception.Message)
End Sub

// The project, which uses this code, must have references to the following assemblies:
// - Vintasoft.Imaging
// - Vintasoft.Imaging.FormsProcessing

/// <summary>
/// Recognizes single image synchronously.
/// </summary>
/// <param name="templateManager">The template manager.</param>
/// <param name="image">The image.</param>
public static void RecognizeSingleImageSync(
    Vintasoft.Imaging.FormsProcessing.FormRecognition.FormTemplateManager templateManager, 
    Vintasoft.Imaging.VintasoftImage image)
{
    // create template matching command
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand templateMatching = 
        new Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand();
    // set minimal confidence
    templateMatching.MinConfidence = 0.6f;
    // set template images
    templateMatching.TemplateImages = templateManager.TemplateImages;
    // create recognition manager
    Vintasoft.Imaging.FormsProcessing.FormRecognitionManager recognitionManager = 
        new Vintasoft.Imaging.FormsProcessing.FormRecognitionManager(
            templateMatching, templateManager);

    // if your form template contains OCR fields,
    // make sure OCR engine manager is initialized before recognition
    // (otherwise recognition will return null (Nothing)),
    // see OCR field recognition examples

    // subscribe to ImageRecognitionError event to output recognition errors
    recognitionManager.ImageRecognitionError += recognitionManager_ImageRecognitionError;

    // recognize the image
    Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult = recognitionManager.Recognize(image);

    // unsubscribe from ImageRecognitionError event
    recognitionManager.ImageRecognitionError -= recognitionManager_ImageRecognitionError;

    // if recognition failed with error (see ImageRecognitionError event handler output)
    if (recognitionResult == null)
        return;

    // get the result of image comparison
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult imageCompareResult =
        recognitionResult.TemplateMatchingResult.ImageCompareResult;
    // if result is not reliable
    if (!imageCompareResult.IsReliable)
    {
        // matching template is not found
        System.Console.WriteLine("Matching template is not found.");
    }
    else
    {
        // get recognized page
        Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage recognizedPage = recognitionResult.RecognizedPage;
        // write page info
        System.Console.WriteLine(string.Format(
            "Matching template: {0}; confidence: {1:F1}%.",
            recognizedPage.Name,
            imageCompareResult.Confidence * 100));

        // get form field count
        if (recognizedPage.Items.Count == 0)
        {
            System.Console.WriteLine("No form fields were recognized.");
        }
        else
        {
            System.Console.WriteLine(string.Format(
                "Recognized form field count: {0}",
                recognizedPage.Items.Count));
            // for each recognized form field
            foreach (Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField recognizedField in recognizedPage.Items)
            {
                // write field info
                System.Console.WriteLine(string.Format(
                    "  Name: {0}; value: {1}; confidence: {2:F1}%",
                    recognizedField.Name,
                    recognizedField.Value,
                    recognizedField.Confidence * 100));
            }
        }
    }
}

/// <summary>
/// Handles the ImageRecognitionError event of the FormRecognitionManager.
/// </summary>
static void recognitionManager_ImageRecognitionError(object sender, 
    Vintasoft.Imaging.FormsProcessing.FormRecognitionErrorEventArgs e)
{
    System.Console.WriteLine(e.Exception.Message);
}

Here is an example that demonstrates how to identify and recognize a form asynchronously.

VB.NET

' The project, which uses this code, must have references to the following assemblies:
' - Vintasoft.Imaging
' - Vintasoft.Imaging.FormsProcessing

''' <summary>
''' Recognizes single image asynchronously.
''' </summary>
''' <param name="templateManager">The template manager.</param>
''' <param name="image">The image.</param>
Public Shared Sub RecognizeSingleImageAsync(templateManager As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormTemplateManager, image As Vintasoft.Imaging.VintasoftImage)
    ' create template matching command
    Dim templateMatching As New Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand()
    ' set minimal confidence
    templateMatching.MinConfidence = 0.6F
    ' set template images
    templateMatching.TemplateImages = templateManager.TemplateImages
    ' create recognition manager
    Dim recognitionManager As New Vintasoft.Imaging.FormsProcessing.FormRecognitionManager(templateMatching, templateManager)

    ' if your form template contains OCR fields,
    ' make sure OCR engine manager is initialized before recognition
    ' (otherwise recognition will return null (Nothing)),
    ' see OCR field recognition examples

    ' create recognition task
    Dim singleImageRecognitionTask As New Vintasoft.Imaging.FormsProcessing.FormRecognitionTask(image)
    ' subscribe to Finished event
    AddHandler singleImageRecognitionTask.Finished, New System.EventHandler(AddressOf singleImageRecognitionTask_Finished)
    ' subscribe to ImageRecognitionError event to output recognition errors
    AddHandler singleImageRecognitionTask.ImageRecognitionError, AddressOf singleImageRecognitionTask_ImageRecognitionError
    ' start recognition of the image
    recognitionManager.RecognizeAsync(singleImageRecognitionTask)
End Sub

''' <summary>
''' Handles the Finished event of the recognition task
''' and outputs the recognition results.
''' </summary>
''' <param name="sender">The source of the event.</param>
''' <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
Private Shared Sub singleImageRecognitionTask_Finished(sender As Object, e As System.EventArgs)
    ' get the recognition task
    Dim task As Vintasoft.Imaging.FormsProcessing.FormRecognitionTask = DirectCast(sender, Vintasoft.Imaging.FormsProcessing.FormRecognitionTask)
    ' get the result of recognition
    Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = task.Results(0)

    ' if recognition failed with error (see ImageRecognitionError event handler output)
    If recognitionResult Is Nothing Then
        Return
    End If

    ' get the result of image comparison
    Dim imageCompareResult As Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult = recognitionResult.TemplateMatchingResult.ImageCompareResult
    ' if result is not reliable
    If Not imageCompareResult.IsReliable Then
        ' matching template is not found
        System.Console.WriteLine("Matching template is not found.")
    Else
        ' get recognized page
        Dim recognizedPage As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage = recognitionResult.RecognizedPage
        ' write page info
        System.Console.WriteLine(String.Format("Matching template: {0}; confidence: {1:F1}%.", recognizedPage.Name, imageCompareResult.Confidence * 100))

        ' get form field count
        If recognizedPage.Items.Count = 0 Then
            System.Console.WriteLine("No form fields were recognized.")
        Else
            System.Console.WriteLine(String.Format("Recognized form field count: {0}", recognizedPage.Items.Count))
            ' for each recognized form field
            For Each recognizedField As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField In recognizedPage.Items
                ' write field info
                System.Console.WriteLine(String.Format("  Name: {0}; value: {1}; confidence: {2:F1}%", recognizedField.Name, recognizedField.Value, recognizedField.Confidence * 100))
            Next
        End If
    End If
End Sub

''' <summary>
''' Handles the ImageRecognitionError event of the FormRecognitionTask.
''' </summary>
Private Shared Sub singleImageRecognitionTask_ImageRecognitionError(sender As Object, e As Vintasoft.Imaging.FormsProcessing.FormRecognitionErrorEventArgs)
    System.Console.WriteLine(e.Exception.Message)
End Sub

// The project, which uses this code, must have references to the following assemblies:
// - Vintasoft.Imaging
// - Vintasoft.Imaging.FormsProcessing

/// <summary>
/// Recognizes single image asynchronously.
/// </summary>
/// <param name="templateManager">The template manager.</param>
/// <param name="image">The image.</param>
public static void RecognizeSingleImageAsync(
    Vintasoft.Imaging.FormsProcessing.FormRecognition.FormTemplateManager templateManager, 
    Vintasoft.Imaging.VintasoftImage image)
{
    // create template matching command
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand templateMatching = 
        new Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand();
    // set minimal confidence
    templateMatching.MinConfidence = 0.6f;
    // set template images
    templateMatching.TemplateImages = templateManager.TemplateImages;
    // create recognition manager
    Vintasoft.Imaging.FormsProcessing.FormRecognitionManager recognitionManager = 
        new Vintasoft.Imaging.FormsProcessing.FormRecognitionManager(
            templateMatching, templateManager);

    // if your form template contains OCR fields,
    // make sure OCR engine manager is initialized before recognition
    // (otherwise recognition will return null (Nothing)),
    // see OCR field recognition examples

    // create recognition task
    Vintasoft.Imaging.FormsProcessing.FormRecognitionTask singleImageRecognitionTask = 
        new Vintasoft.Imaging.FormsProcessing.FormRecognitionTask(image);
    // subscribe to Finished event
    singleImageRecognitionTask.Finished += 
        new System.EventHandler(singleImageRecognitionTask_Finished);
    // subscribe to ImageRecognitionError event to output recognition errors
    singleImageRecognitionTask.ImageRecognitionError += singleImageRecognitionTask_ImageRecognitionError;
    // start recognition of the image
    recognitionManager.RecognizeAsync(singleImageRecognitionTask);
}

/// <summary>
/// Handles the Finished event of the recognition task
/// and outputs the recognition results.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
private static void singleImageRecognitionTask_Finished(object sender, System.EventArgs e)
{
    // get the recognition task
    Vintasoft.Imaging.FormsProcessing.FormRecognitionTask task = 
        (Vintasoft.Imaging.FormsProcessing.FormRecognitionTask)sender;
    // get the result of recognition
    Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult = task.Results[0];

    // if recognition failed with error (see ImageRecognitionError event handler output)
    if (recognitionResult == null)
        return;

    // get the result of image comparison
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult imageCompareResult =
        recognitionResult.TemplateMatchingResult.ImageCompareResult;
    // if result is not reliable
    if (!imageCompareResult.IsReliable)
    {
        // matching template is not found
        System.Console.WriteLine("Matching template is not found.");
    }
    else
    {
        // get recognized page
        Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage recognizedPage = recognitionResult.RecognizedPage;
        // write page info
        System.Console.WriteLine(string.Format(
            "Matching template: {0}; confidence: {1:F1}%.",
            recognizedPage.Name,
            imageCompareResult.Confidence * 100));

        // get form field count
        if (recognizedPage.Items.Count == 0)
        {
            System.Console.WriteLine("No form fields were recognized.");
        }
        else
        {
            System.Console.WriteLine(string.Format(
                "Recognized form field count: {0}",
                recognizedPage.Items.Count));
            // for each recognized form field
            foreach (Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField recognizedField in recognizedPage.Items)
            {
                // write field info
                System.Console.WriteLine(string.Format(
                    "  Name: {0}; value: {1}; confidence: {2:F1}%",
                    recognizedField.Name,
                    recognizedField.Value,
                    recognizedField.Confidence * 100));
            }
        }
    }
}

/// <summary>
/// Handles the ImageRecognitionError event of the FormRecognitionTask.
/// </summary>
static void singleImageRecognitionTask_ImageRecognitionError(object sender, 
    Vintasoft.Imaging.FormsProcessing.FormRecognitionErrorEventArgs e)
{
    System.Console.WriteLine(e.Exception.Message);
}

Identify and recognize a document that contains several forms

For identification and recognition of document that contains several forms is necessary to do the following:

Identify templates of all forms
Perform the forms recognition

Here is an example that demonstrates how to identify and recognize several forms asynchronously.

VB.NET

' The project, which uses this code, must have references to the following assemblies:
' - Vintasoft.Imaging
' - Vintasoft.Imaging.FormsProcessing

''' <summary>
''' Recognizes array of images synchronously.
''' </summary>
''' <param name="templateManager">The template manager.</param>
''' <param name="images">The images.</param>
Public Shared Sub RecognizeImagesSync(templateManager As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormTemplateManager, images As Vintasoft.Imaging.VintasoftImage())
    ' create template matching command
    Dim templateMatching As New Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand()
    ' set minimal confidence
    templateMatching.MinConfidence = 0.6F
    ' set template images
    templateMatching.TemplateImages = templateManager.TemplateImages
    ' create recognition manager
    Dim recognitionManager As New Vintasoft.Imaging.FormsProcessing.FormRecognitionManager(templateMatching, templateManager)

    ' if your form template contains OCR fields,
    ' make sure OCR engine manager is initialized before recognition
    ' (otherwise recognition will return null (Nothing)),
    ' see OCR field recognition examples

    ' subscribe to ImageRecognitionError event to output recognition errors
    AddHandler recognitionManager.ImageRecognitionError, AddressOf manager_ImageRecognitionError
    ' recognize the images
    Dim recognitionResults As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult() = recognitionManager.Recognize(images)
    ' unsubscribe from ImageRecognitionError event
    RemoveHandler recognitionManager.ImageRecognitionError, AddressOf manager_ImageRecognitionError
    ' for each recognition result
    For i As Integer = 0 To recognitionResults.Length - 1
        System.Console.WriteLine(String.Format("Image {0} of {1}:", i + 1, recognitionResults.Length))
        System.Console.WriteLine()

        Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = recognitionResults(i)

        ' if recognition failed with error (see ImageRecognitionError event handler output)
        If recognitionResult Is Nothing Then
            Continue For
        End If

        ' get the result of image comparison
        Dim imageCompareResult As Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult = recognitionResult.TemplateMatchingResult.ImageCompareResult
        ' if result is not reliable
        If Not imageCompareResult.IsReliable Then
            ' matching template is not found
            System.Console.WriteLine("Matching template is not found.")
        Else
            ' get recognized page
            Dim recognizedPage As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage = recognitionResult.RecognizedPage
            ' write page info
            System.Console.WriteLine(String.Format("Matching template: {0}; confidence: {1:F1}%.", recognizedPage.Name, imageCompareResult.Confidence * 100))

            ' get form field count
            If recognizedPage.Items.Count = 0 Then
                System.Console.WriteLine("No form fields were recognized.")
            Else
                System.Console.WriteLine(String.Format("Recognized form field count: {0}", recognizedPage.Items.Count))
                ' for each recognized form field
                For Each recognizedField As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField In recognizedPage.Items
                    ' write field info
                    System.Console.WriteLine(String.Format("  Name: {0}; value: {1}; confidence: {2:F1}%", recognizedField.Name, recognizedField.Value, recognizedField.Confidence * 100))
                Next
            End If
        End If

        System.Console.WriteLine()
        System.Console.WriteLine()
    Next
End Sub

''' <summary>
''' Handles the ImageRecognitionError event of the FormRecognitionManager.
''' </summary>
Private Shared Sub manager_ImageRecognitionError(sender As Object, e As Vintasoft.Imaging.FormsProcessing.FormRecognitionErrorEventArgs)
    System.Console.WriteLine(e.Exception.Message)
End Sub

// The project, which uses this code, must have references to the following assemblies:
// - Vintasoft.Imaging
// - Vintasoft.Imaging.FormsProcessing

/// <summary>
/// Recognizes array of images synchronously.
/// </summary>
/// <param name="templateManager">The template manager.</param>
/// <param name="images">The images.</param>
public static void RecognizeImagesSync(
    Vintasoft.Imaging.FormsProcessing.FormRecognition.FormTemplateManager templateManager, 
    Vintasoft.Imaging.VintasoftImage[] images)
{
    // create template matching command
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand templateMatching = 
        new Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand();
    // set minimal confidence
    templateMatching.MinConfidence = 0.6f;
    // set template images
    templateMatching.TemplateImages = templateManager.TemplateImages;
    // create recognition manager
    Vintasoft.Imaging.FormsProcessing.FormRecognitionManager recognitionManager = 
        new Vintasoft.Imaging.FormsProcessing.FormRecognitionManager(
            templateMatching, templateManager);

    // if your form template contains OCR fields,
    // make sure OCR engine manager is initialized before recognition
    // (otherwise recognition will return null (Nothing)),
    // see OCR field recognition examples

    // subscribe to ImageRecognitionError event to output recognition errors
    recognitionManager.ImageRecognitionError += manager_ImageRecognitionError;
    // recognize the images
    Vintasoft.Imaging.FormsProcessing.FormRecognitionResult[] recognitionResults = recognitionManager.Recognize(images);
    // unsubscribe from ImageRecognitionError event
    recognitionManager.ImageRecognitionError -= manager_ImageRecognitionError;
    // for each recognition result
    for (int i = 0; i < recognitionResults.Length; i++)
    {
        System.Console.WriteLine(string.Format(
            "Image {0} of {1}:",
            i + 1,
            recognitionResults.Length));
        System.Console.WriteLine();

        Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult = recognitionResults[i];

        // if recognition failed with error (see ImageRecognitionError event handler output)
        if (recognitionResult == null)
            continue;

        // get the result of image comparison
        Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult imageCompareResult =
            recognitionResult.TemplateMatchingResult.ImageCompareResult;
        // if result is not reliable
        if (!imageCompareResult.IsReliable)
        {
            // matching template is not found
            System.Console.WriteLine("Matching template is not found.");
        }
        else
        {
            // get recognized page
            Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage recognizedPage = recognitionResult.RecognizedPage;
            // write page info
            System.Console.WriteLine(string.Format(
                "Matching template: {0}; confidence: {1:F1}%.",
                recognizedPage.Name,
                imageCompareResult.Confidence * 100));

            // get form field count
            if (recognizedPage.Items.Count == 0)
            {
                System.Console.WriteLine("No form fields were recognized.");
            }
            else
            {
                System.Console.WriteLine(string.Format(
                    "Recognized form field count: {0}",
                    recognizedPage.Items.Count));
                // for each recognized form field
                foreach (Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField recognizedField in recognizedPage.Items)
                {
                    // write field info
                    System.Console.WriteLine(string.Format(
                        "  Name: {0}; value: {1}; confidence: {2:F1}%",
                        recognizedField.Name,
                        recognizedField.Value,
                        recognizedField.Confidence * 100));
                }
            }
        }

        System.Console.WriteLine();
        System.Console.WriteLine();
    }
}

/// <summary>
/// Handles the ImageRecognitionError event of the FormRecognitionManager.
/// </summary>
static void manager_ImageRecognitionError(object sender, 
    Vintasoft.Imaging.FormsProcessing.FormRecognitionErrorEventArgs e)
{
    System.Console.WriteLine(e.Exception.Message);
}

Identify and recognize a document that contains forms with marks

For identification and recognition of document that contains forms with marks is necessary to do the following:

Identify templates of all forms
Perform the forms recognition

Here is an example that demonstrates how to identify and recognize a form, that contains marks.

VB.NET

' The project, which uses this code, must have references to the following assemblies:
' - Vintasoft.Imaging
' - Vintasoft.Imaging.FormsProcessing

''' <summary>
''' Recognizes the form with OMR fields.
''' </summary>
''' <param name="formRecognitionManager">The form recognition manager.</param>
''' <param name="image">The image.</param>
Public Shared Sub RecognizeFormWithOmrFields(formRecognitionManager As Vintasoft.Imaging.FormsProcessing.FormRecognitionManager, image As Vintasoft.Imaging.VintasoftImage)
    ' if your form template contains OCR fields,
    ' make sure OCR engine manager is initialized before recognition
    ' (otherwise recognition will return null (Nothing)),
    ' see OCR field recognition examples

    ' recognize the image
    Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = formRecognitionManager.Recognize(image)

    ' get the result of image comparison
    Dim imageCompareResult As Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult = recognitionResult.TemplateMatchingResult.ImageCompareResult
    ' if result is not reliable
    If Not imageCompareResult.IsReliable Then
        ' matching template is not found
        System.Console.WriteLine("Matching template is not found.")
    Else
        ' get recognized page
        Dim recognizedPage As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage = recognitionResult.RecognizedPage
        ' get form field count
        If recognizedPage.Items.Count = 0 Then
            System.Console.WriteLine("No form fields were recognized.")
        Else
            System.Console.WriteLine(String.Format("Recognized form field count: {0}", recognizedPage.Items.Count))
            ' for each recognized form field
            For Each recognizedField As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField In recognizedPage.Items
                If TypeOf recognizedField Is Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrField Then
                    Dim omrField As Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrField = DirectCast(recognizedField, Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrField)
                    ' write field info
                    System.Console.WriteLine(String.Format("  OMR field: name: {0}; state: {1}; confidence: {2:F1}%", omrField.Name, omrField.State, omrField.Confidence * 100))
                End If
            Next
        End If
    End If
End Sub

// The project, which uses this code, must have references to the following assemblies:
// - Vintasoft.Imaging
// - Vintasoft.Imaging.FormsProcessing

/// <summary>
/// Recognizes the form with OMR fields.
/// </summary>
/// <param name="formRecognitionManager">The form recognition manager.</param>
/// <param name="image">The image.</param>
public static void RecognizeFormWithOmrFields(
    Vintasoft.Imaging.FormsProcessing.FormRecognitionManager formRecognitionManager,
    Vintasoft.Imaging.VintasoftImage image)
{
    // if your form template contains OCR fields,
    // make sure OCR engine manager is initialized before recognition
    // (otherwise recognition will return null (Nothing)),
    // see OCR field recognition examples

    // recognize the image
    Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult = 
        formRecognitionManager.Recognize(image);

    // get the result of image comparison
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult imageCompareResult =
        recognitionResult.TemplateMatchingResult.ImageCompareResult;
    // if result is not reliable
    if (!imageCompareResult.IsReliable)
    {
        // matching template is not found
        System.Console.WriteLine("Matching template is not found.");
    }
    else
    {
        // get recognized page
        Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage recognizedPage = 
            recognitionResult.RecognizedPage;
        // get form field count
        if (recognizedPage.Items.Count == 0)
        {
            System.Console.WriteLine("No form fields were recognized.");
        }
        else
        {
            System.Console.WriteLine(string.Format(
                "Recognized form field count: {0}",
                recognizedPage.Items.Count));
            // for each recognized form field
            foreach (Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField recognizedField in recognizedPage.Items)
            {
                if (recognizedField is Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrField)
                {
                    Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrField omrField = 
                        (Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrField)recognizedField;
                    // write field info
                    System.Console.WriteLine(string.Format(
                        "  OMR field: name: {0}; state: {1}; confidence: {2:F1}%",
                        omrField.Name,
                        omrField.State,
                        omrField.Confidence * 100));
                }
            }
        }
    }
}

Here is an example that demonstrates how to identify and recognize a form, that contains bubble sheet (group of marks).

VB.NET

' The project, which uses this code, must have references to the following assemblies:
' - Vintasoft.Imaging
' - Vintasoft.Imaging.FormsProcessing

''' <summary>
''' Recognizes the form with a group of marks (OMR bubbles).
''' </summary>
''' <param name="formRecognitionManager">The form recognition manager.</param>
''' <param name="image">The image.</param>
Public Shared Sub RecognizeFormWithOmrFieldTables(formRecognitionManager As Vintasoft.Imaging.FormsProcessing.FormRecognitionManager, image As Vintasoft.Imaging.VintasoftImage)
    ' if your form template contains OCR fields,
    ' make sure OCR engine manager is initialized before recognition
    ' (otherwise recognition will return null (Nothing)),
    ' see OCR field recognition examples

    ' recognize the image
    Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = formRecognitionManager.Recognize(image)

    ' get the result of image comparison
    Dim imageCompareResult As Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult = recognitionResult.TemplateMatchingResult.ImageCompareResult
    ' if result is not reliable
    If Not imageCompareResult.IsReliable Then
        ' matching template is not found
        System.Console.WriteLine("Matching template is not found.")
    Else
        ' get recognized page
        Dim recognizedPage As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage = recognitionResult.RecognizedPage
        ' get form field count
        If recognizedPage.Items.Count = 0 Then
            System.Console.WriteLine("No form fields were recognized.")
        Else
            System.Console.WriteLine(String.Format("Recognized form field count: {0}", recognizedPage.Items.Count))
            ' for each recognized form field
            For Each recognizedField As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField In recognizedPage.Items
                If TypeOf recognizedField Is Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrFieldTable Then
                    Dim omrFieldTable As Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrFieldTable = DirectCast(recognizedField, Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrFieldTable)
                    Dim omrTemplateTable As Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrFieldTemplateTable = TryCast(omrFieldTable.FieldTemplate, Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrFieldTemplateTable)
                    ' write field info
                    System.Console.WriteLine(String.Format("  OMR field table: name: {0}; value: {1}; confidence: {2:F1}%; row count: {3}; column count: {4}", omrFieldTable.Name, omrFieldTable.Value, omrFieldTable.Confidence * 100, omrTemplateTable.RowCount, omrTemplateTable.ColumnCount))
                End If
            Next
        End If
    End If
End Sub

// The project, which uses this code, must have references to the following assemblies:
// - Vintasoft.Imaging
// - Vintasoft.Imaging.FormsProcessing

/// <summary>
/// Recognizes the form with a group of marks (OMR bubbles).
/// </summary>
/// <param name="formRecognitionManager">The form recognition manager.</param>
/// <param name="image">The image.</param>
public static void RecognizeFormWithOmrFieldTables(
    Vintasoft.Imaging.FormsProcessing.FormRecognitionManager formRecognitionManager,
    Vintasoft.Imaging.VintasoftImage image)
{
    // if your form template contains OCR fields,
    // make sure OCR engine manager is initialized before recognition
    // (otherwise recognition will return null (Nothing)),
    // see OCR field recognition examples

    // recognize the image
    Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult = 
        formRecognitionManager.Recognize(image);

    // get the result of image comparison
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult imageCompareResult =
        recognitionResult.TemplateMatchingResult.ImageCompareResult;
    // if result is not reliable
    if (!imageCompareResult.IsReliable)
    {
        // matching template is not found
        System.Console.WriteLine("Matching template is not found.");
    }
    else
    {
        // get recognized page
        Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage recognizedPage = 
            recognitionResult.RecognizedPage;
        // get form field count
        if (recognizedPage.Items.Count == 0)
        {
            System.Console.WriteLine("No form fields were recognized.");
        }
        else
        {
            System.Console.WriteLine(string.Format(
                "Recognized form field count: {0}",
                recognizedPage.Items.Count));
            // for each recognized form field
            foreach (Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField recognizedField in recognizedPage.Items)
            {
                if (recognizedField is Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrFieldTable)
                {
                    Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrFieldTable omrFieldTable = 
                        (Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrFieldTable)recognizedField;
                    Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrFieldTemplateTable omrTemplateTable =
                        omrFieldTable.FieldTemplate as Vintasoft.Imaging.FormsProcessing.FormRecognition.Omr.OmrFieldTemplateTable;
                    // write field info
                    System.Console.WriteLine(string.Format(
                        "  OMR field table: name: {0}; value: {1}; confidence: {2:F1}%; row count: {3}; column count: {4}",
                        omrFieldTable.Name,
                        omrFieldTable.Value,
                        omrFieldTable.Confidence * 100,
                        omrTemplateTable.RowCount,
                        omrTemplateTable.ColumnCount));
                }
            }
        }
    }
}

Identify and recognize a document that contains forms with text

For identification and recognition of document that contains forms with text is necessary to do the following:

Identify templates of all forms.
Specify the OCR engine that must be used for text recognition. The OcrFieldTemplate.OcrEngineManager property allows to specify OCR engine, which must be used for recognizing text in OCR fields.
Perform the forms recognition.

Here is an example that demonstrates how to identify and recognize a form, that contains text.

VB.NET

' The project, which uses this code, must have references to the following assemblies:
' - Vintasoft.Imaging
' - Vintasoft.Imaging.FormsProcessing
' - Vintasoft.Imaging.FormsProcessing.Ocr
' - Vintasoft.Imaging.Ocr
' - Vintasoft.Imaging.Ocr.Tesseract

''' <summary>
''' Recognizes the form with OCR fields.
''' </summary>
''' <param name="formRecognitionManager">The form recognition manager.</param>
''' <param name="image">The image.</param>
Public Shared Sub RecognizeFormWithOcrFields(formRecognitionManager As Vintasoft.Imaging.FormsProcessing.FormRecognitionManager, image As Vintasoft.Imaging.VintasoftImage)
    ' check whether OCR engine manager of the OCR field templates is initialized
    ' (this initialization can be moved to the start of your application)
    If Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrFieldTemplate.OcrEngineManager Is Nothing Then
        ' get or create OCR engine
        Dim ocrEngine As Vintasoft.Imaging.Ocr.OcrEngine = GetOcrEngine()
        ' create and set OCR engine manager of the OCR field templates
        Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrFieldTemplate.OcrEngineManager = New Vintasoft.Imaging.Ocr.OcrEngineManager(ocrEngine)
    End If

    ' recognize the image
    Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = formRecognitionManager.Recognize(image)

    ' get the result of image comparison
    Dim imageCompareResult As Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult = recognitionResult.TemplateMatchingResult.ImageCompareResult
    ' if result is not reliable
    If Not imageCompareResult.IsReliable Then
        ' matching template is not found
        System.Console.WriteLine("Matching template is not found.")
    Else
        ' get recognized page
        Dim recognizedPage As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage = recognitionResult.RecognizedPage
        ' get form field count
        If recognizedPage.Items.Count = 0 Then
            System.Console.WriteLine("No form fields were recognized.")
        Else
            System.Console.WriteLine(String.Format("Recognized form field count: {0}", recognizedPage.Items.Count))
            ' for each recognized form field
            For Each recognizedField As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField In recognizedPage.Items
                If TypeOf recognizedField Is Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField Then
                    Dim ocrField As Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField = DirectCast(recognizedField, Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField)
                    ' write field info
                    System.Console.WriteLine(String.Format("  OCR field: name: {0}; value: {1}; confidence: {2:F1}%", ocrField.Name, ocrField.Value, ocrField.Confidence * 100))
                    Dim ocrResult As Vintasoft.Imaging.Ocr.Results.OcrPage = ocrField.OcrResult
                    ' get all words
                    Dim words As Vintasoft.Imaging.Ocr.Results.OcrObject() = ocrResult.GetWords(75, 75)
                    ' write words info
                    For i As Integer = 0 To words.Length - 1
                        Dim word As Vintasoft.Imaging.Ocr.Results.OcrObject = words(i)
                        System.Console.WriteLine(String.Format("    OCR word: {0}; confidence: {1:F1}%", word.ToString(), word.Confidence))
                    Next
                End If
            Next
        End If
    End If
End Sub

''' <summary>
''' Gets the OCR engine used for OCR field recognition.
''' </summary>
''' <remarks>
''' To create a Tesseract OCR engine,
''' add a reference to Vintasoft.Imaging.Ocr.Tesseract.dll
''' into your project.
''' </remarks>
Private Shared Function GetOcrEngine() As Vintasoft.Imaging.Ocr.OcrEngine
    ' full path to the Tesseract4.Vintasoft.xXX.dll files
    ' NOTE: specify here the actual path to the Tesseract OCR dll files
    Dim tesseractDllDirectory As String = "C:\Program Files\VintaSoft\VintaSoft Imaging .NET\Bin\TesseractOCR\"
    ' create Tesseract OCR engine (Vintasoft.Imaging.Ocr.Tesseract.dll is required)
    Return New Vintasoft.Imaging.Ocr.Tesseract.TesseractOcr(tesseractDllDirectory)
End Function

// The project, which uses this code, must have references to the following assemblies:
// - Vintasoft.Imaging
// - Vintasoft.Imaging.FormsProcessing
// - Vintasoft.Imaging.FormsProcessing.Ocr
// - Vintasoft.Imaging.Ocr
// - Vintasoft.Imaging.Ocr.Tesseract

/// <summary>
/// Recognizes the form with OCR fields.
/// </summary>
/// <param name="formRecognitionManager">The form recognition manager.</param>
/// <param name="image">The image.</param>
public static void RecognizeFormWithOcrFields(
    Vintasoft.Imaging.FormsProcessing.FormRecognitionManager formRecognitionManager,
    Vintasoft.Imaging.VintasoftImage image)
{
    // check whether OCR engine manager of the OCR field templates is initialized
    // (this initialization can be moved to the start of your application)
    if (Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrFieldTemplate.OcrEngineManager == null)
    {
        // get or create OCR engine
        Vintasoft.Imaging.Ocr.OcrEngine ocrEngine = GetOcrEngine();
        // create and set OCR engine manager of the OCR field templates
        Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrFieldTemplate.OcrEngineManager = 
            new Vintasoft.Imaging.Ocr.OcrEngineManager(ocrEngine);
    }

    // recognize the image
    Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult = 
        formRecognitionManager.Recognize(image);

    // get the result of image comparison
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult imageCompareResult =
        recognitionResult.TemplateMatchingResult.ImageCompareResult;
    // if result is not reliable
    if (!imageCompareResult.IsReliable)
    {
        // matching template is not found
        System.Console.WriteLine("Matching template is not found.");
    }
    else
    {
        // get recognized page
        Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage recognizedPage = recognitionResult.RecognizedPage;
        // get form field count
        if (recognizedPage.Items.Count == 0)
        {
            System.Console.WriteLine("No form fields were recognized.");
        }
        else
        {
            System.Console.WriteLine(string.Format(
                "Recognized form field count: {0}",
                recognizedPage.Items.Count));
            // for each recognized form field
            foreach (Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField recognizedField in recognizedPage.Items)
            {
                if (recognizedField is Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField)
                {
                    Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField ocrField = 
                        (Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField)recognizedField;
                    // write field info
                    System.Console.WriteLine(string.Format(
                        "  OCR field: name: {0}; value: {1}; confidence: {2:F1}%",
                        ocrField.Name,
                        ocrField.Value,
                        ocrField.Confidence * 100));
                    Vintasoft.Imaging.Ocr.Results.OcrPage ocrResult = ocrField.OcrResult;
                    // get all words
                    Vintasoft.Imaging.Ocr.Results.OcrObject[] words = ocrResult.GetWords(75, 75);
                    // write words info
                    for (int i = 0; i < words.Length; i++)
                    {
                        Vintasoft.Imaging.Ocr.Results.OcrObject word = words[i];
                        System.Console.WriteLine(string.Format(
                            "    OCR word: {0}; confidence: {1:F1}%",
                            word.ToString(),
                            word.Confidence));
                    }
                }
            }
        }
    }
}

/// <summary>
/// Gets the OCR engine used for OCR field recognition.
/// </summary>
/// <remarks>
/// To create a Tesseract OCR engine,
/// add a reference to Vintasoft.Imaging.Ocr.Tesseract.dll
/// into your project.
/// </remarks>
private static Vintasoft.Imaging.Ocr.OcrEngine GetOcrEngine()
{
    // full path to the Tesseract4.Vintasoft.xXX.dll files
    // NOTE: specify here the actual path to the Tesseract OCR dll files
    string tesseractDllDirectory = @"C:\Program Files\VintaSoft\VintaSoft Imaging .NET\Bin\TesseractOCR\";
    // create Tesseract OCR engine (Vintasoft.Imaging.Ocr.Tesseract.dll is required)
    return new Vintasoft.Imaging.Ocr.Tesseract.TesseractOcr(tesseractDllDirectory);
}

Identify and recognize a document that contains forms with barcodes

For identification and recognition of document that contains forms with barcodes is necessary to do the following:

Identify templates of all forms
Perform the forms recognition

Here is an example that demonstrates how to identify and recognize a form, that contains barcodes.

VB.NET

' The project, which uses this code, must have references to the following assemblies:
' - Vintasoft.Imaging
' - Vintasoft.Imaging.FormsProcessing

''' <summary>
''' Recognizes the form with barcode fields.
''' </summary>
''' <param name="formRecognitionManager">The form recognition manager.</param>
''' <param name="image">The image.</param>
''' <remarks>
''' The BarcodeField and BarcodeFieldTemplate classes are available
''' in the VintaSoft Forms Processing Demo source codes.
''' </remarks>
Public Shared Sub RecognizeFormWithBarcodeFields(formRecognitionManager As Vintasoft.Imaging.FormsProcessing.FormRecognitionManager, image As Vintasoft.Imaging.VintasoftImage)
    ' if your form template contains OCR fields,
    ' make sure OCR engine manager is initialized before recognition
    ' (otherwise recognition will return null (Nothing)),
    ' see OCR field recognition examples

    ' recognize the image
    Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = formRecognitionManager.Recognize(image)

    ' get the result of image comparison
    Dim imageCompareResult As Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult = recognitionResult.TemplateMatchingResult.ImageCompareResult
    ' if result is not reliable
    If Not imageCompareResult.IsReliable Then
        ' matching template is not found
        System.Console.WriteLine("Matching template is not found.")
    Else
        ' get recognized page
        Dim recognizedPage As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage = recognitionResult.RecognizedPage
        ' get form field count
        If recognizedPage.Items.Count = 0 Then
            System.Console.WriteLine("No form fields were recognized.")
        Else
            System.Console.WriteLine(String.Format("Recognized form field count: {0}", recognizedPage.Items.Count))
            ' for each recognized form field
            For Each recognizedField As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField In recognizedPage.Items
                ' an example of BarcodeField class implementation can be found
                ' in the VintaSoft Forms Processing Demo source codes
                If TypeOf recognizedField Is BarcodeField Then
                    Dim barcodeField As BarcodeField = DirectCast(recognizedField, BarcodeField)
                    ' write field info
                    System.Console.WriteLine(String.Format("  Barcode field: name: {0}; type: {1}; value: {2}; confidence: {3:F1}%", barcodeField.Name, barcodeField.BarcodeInfo.BarcodeType, barcodeField.Value, barcodeField.Confidence * 100))
                End If
            Next
        End If
    End If
End Sub

// The project, which uses this code, must have references to the following assemblies:
// - Vintasoft.Imaging
// - Vintasoft.Imaging.FormsProcessing

/// <summary>
/// Recognizes the form with barcode fields.
/// </summary>
/// <param name="formRecognitionManager">The form recognition manager.</param>
/// <param name="image">The image.</param>
/// <remarks>
/// The BarcodeField and BarcodeFieldTemplate classes are available
/// in the VintaSoft Forms Processing Demo source codes.
/// </remarks>
public static void RecognizeFormWithBarcodeFields(
    Vintasoft.Imaging.FormsProcessing.FormRecognitionManager formRecognitionManager,
    Vintasoft.Imaging.VintasoftImage image)
{
    // if your form template contains OCR fields,
    // make sure OCR engine manager is initialized before recognition
    // (otherwise recognition will return null (Nothing)),
    // see OCR field recognition examples

    // recognize the image
    Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult = 
        formRecognitionManager.Recognize(image);

    // get the result of image comparison
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult imageCompareResult =
        recognitionResult.TemplateMatchingResult.ImageCompareResult;
    // if result is not reliable
    if (!imageCompareResult.IsReliable)
    {
        // matching template is not found
        System.Console.WriteLine("Matching template is not found.");
    }
    else
    {
        // get recognized page
        Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage recognizedPage = 
            recognitionResult.RecognizedPage;
        // get form field count
        if (recognizedPage.Items.Count == 0)
        {
            System.Console.WriteLine("No form fields were recognized.");
        }
        else
        {
            System.Console.WriteLine(string.Format(
                "Recognized form field count: {0}",
                recognizedPage.Items.Count));
            // for each recognized form field
            foreach (Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField recognizedField in recognizedPage.Items)
            {
                // an example of BarcodeField class implementation can be found
                // in the VintaSoft Forms Processing Demo source codes
                if (recognizedField is BarcodeField)
                {
                    BarcodeField barcodeField = (BarcodeField)recognizedField;
                    // write field info
                    System.Console.WriteLine(string.Format(
                        "  Barcode field: name: {0}; type: {1}; value: {2}; confidence: {3:F1}%",
                        barcodeField.Name,
                        barcodeField.BarcodeInfo.BarcodeType,
                        barcodeField.Value,
                        barcodeField.Confidence * 100));
                }
            }
        }
    }
}

Process template form image and filled form image before form identification and recognition

Sometimes template form image and filled form images are not "ideal" and SDK allows to specify a list of image processing commands, which must be applied to the template form image and filled form image before form identification.

Here is an example that demonstrates how to process form images before form identification (remove noise and apply Dilate command), identify and recognize the form:

VB.NET

' The project, which uses this code, must have references to the following assemblies:
' - Vintasoft.Imaging
' - Vintasoft.Imaging.FormsProcessing

''' <summary>
''' Recognizes single image synchronously.
''' </summary>
''' <param name="templateManager">The template manager.</param>
''' <param name="image">The image.</param>
Public Shared Sub RecognizeSingleImageSync(templateManager As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormTemplateManager, image As Vintasoft.Imaging.VintasoftImage)
    ' create template matching command
    Dim templateMatching As New Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand()
    ' set minimal confidence
    templateMatching.MinConfidence = 0.6F
    ' set template images
    templateMatching.TemplateImages = templateManager.TemplateImages
    ' create recognition manager
    Dim recognitionManager As New Vintasoft.Imaging.FormsProcessing.FormRecognitionManager(templateMatching, templateManager)

    ' if your form template contains OCR fields,
    ' make sure OCR engine manager is initialized before recognition
    ' (otherwise recognition will return null (Nothing)),
    ' see OCR field recognition examples

    ' subscribe to ImageRecognitionError event to output recognition errors
    AddHandler recognitionManager.ImageRecognitionError, AddressOf recognitionManager_ImageRecognitionError

    ' recognize the image
    Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = recognitionManager.Recognize(image)

    ' unsubscribe from ImageRecognitionError event
    RemoveHandler recognitionManager.ImageRecognitionError, AddressOf recognitionManager_ImageRecognitionError

    ' if recognition failed with error (see ImageRecognitionError event handler output)
    If recognitionResult Is Nothing Then
        Return
    End If

    ' get the result of image comparison
    Dim imageCompareResult As Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult = recognitionResult.TemplateMatchingResult.ImageCompareResult
    ' if result is not reliable
    If Not imageCompareResult.IsReliable Then
        ' matching template is not found
        System.Console.WriteLine("Matching template is not found.")
    Else
        ' get recognized page
        Dim recognizedPage As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage = recognitionResult.RecognizedPage
        ' write page info
        System.Console.WriteLine(String.Format("Matching template: {0}; confidence: {1:F1}%.", recognizedPage.Name, imageCompareResult.Confidence * 100))

        ' get form field count
        If recognizedPage.Items.Count = 0 Then
            System.Console.WriteLine("No form fields were recognized.")
        Else
            System.Console.WriteLine(String.Format("Recognized form field count: {0}", recognizedPage.Items.Count))
            ' for each recognized form field
            For Each recognizedField As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField In recognizedPage.Items
                ' write field info
                System.Console.WriteLine(String.Format("  Name: {0}; value: {1}; confidence: {2:F1}%", recognizedField.Name, recognizedField.Value, recognizedField.Confidence * 100))
            Next
        End If
    End If
End Sub

''' <summary>
''' Handles the ImageRecognitionError event of the FormRecognitionManager.
''' </summary>
Private Shared Sub recognitionManager_ImageRecognitionError(sender As Object, e As Vintasoft.Imaging.FormsProcessing.FormRecognitionErrorEventArgs)
    System.Console.WriteLine(e.Exception.Message)
End Sub

// The project, which uses this code, must have references to the following assemblies:
// - Vintasoft.Imaging
// - Vintasoft.Imaging.FormsProcessing

/// <summary>
/// Recognizes single image synchronously.
/// </summary>
/// <param name="templateManager">The template manager.</param>
/// <param name="image">The image.</param>
public static void RecognizeSingleImageSync(
    Vintasoft.Imaging.FormsProcessing.FormRecognition.FormTemplateManager templateManager, 
    Vintasoft.Imaging.VintasoftImage image)
{
    // create template matching command
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand templateMatching = 
        new Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand();
    // set minimal confidence
    templateMatching.MinConfidence = 0.6f;
    // set template images
    templateMatching.TemplateImages = templateManager.TemplateImages;
    // create recognition manager
    Vintasoft.Imaging.FormsProcessing.FormRecognitionManager recognitionManager = 
        new Vintasoft.Imaging.FormsProcessing.FormRecognitionManager(
            templateMatching, templateManager);

    // if your form template contains OCR fields,
    // make sure OCR engine manager is initialized before recognition
    // (otherwise recognition will return null (Nothing)),
    // see OCR field recognition examples

    // subscribe to ImageRecognitionError event to output recognition errors
    recognitionManager.ImageRecognitionError += recognitionManager_ImageRecognitionError;

    // recognize the image
    Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult = recognitionManager.Recognize(image);

    // unsubscribe from ImageRecognitionError event
    recognitionManager.ImageRecognitionError -= recognitionManager_ImageRecognitionError;

    // if recognition failed with error (see ImageRecognitionError event handler output)
    if (recognitionResult == null)
        return;

    // get the result of image comparison
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult imageCompareResult =
        recognitionResult.TemplateMatchingResult.ImageCompareResult;
    // if result is not reliable
    if (!imageCompareResult.IsReliable)
    {
        // matching template is not found
        System.Console.WriteLine("Matching template is not found.");
    }
    else
    {
        // get recognized page
        Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage recognizedPage = recognitionResult.RecognizedPage;
        // write page info
        System.Console.WriteLine(string.Format(
            "Matching template: {0}; confidence: {1:F1}%.",
            recognizedPage.Name,
            imageCompareResult.Confidence * 100));

        // get form field count
        if (recognizedPage.Items.Count == 0)
        {
            System.Console.WriteLine("No form fields were recognized.");
        }
        else
        {
            System.Console.WriteLine(string.Format(
                "Recognized form field count: {0}",
                recognizedPage.Items.Count));
            // for each recognized form field
            foreach (Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField recognizedField in recognizedPage.Items)
            {
                // write field info
                System.Console.WriteLine(string.Format(
                    "  Name: {0}; value: {1}; confidence: {2:F1}%",
                    recognizedField.Name,
                    recognizedField.Value,
                    recognizedField.Confidence * 100));
            }
        }
    }
}

/// <summary>
/// Handles the ImageRecognitionError event of the FormRecognitionManager.
/// </summary>
static void recognitionManager_ImageRecognitionError(object sender, 
    Vintasoft.Imaging.FormsProcessing.FormRecognitionErrorEventArgs e)
{
    System.Console.WriteLine(e.Exception.Message);
}

Display the recognized filled form on image in WinForms image viewer

FormFieldViewerTool class is intended for displaying the recognized filled form on image in WinForms image viewer.
Here is an example that demonstrates how to recognize a form and display the results in WinForms image viewer.

VB.NET

' The project, which uses this code, must have references to the following assemblies:
' - Vintasoft.Imaging
' - Vintasoft.Imaging.FormsProcessing

''' <summary>
''' Recognizes the current image of specified viewer
''' and shows recognition results in viewer.
''' </summary>
''' <param name="viewer">The viewer.</param>
''' <param name="formRecognitionManager">The form recognition manager.</param>
Public Shared Function RecognizeAndShowInViewer(viewer As Vintasoft.Imaging.UI.ImageViewer, formRecognitionManager As Vintasoft.Imaging.FormsProcessing.FormRecognitionManager) As Boolean
    ' recognize the image
    Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = formRecognitionManager.Recognize(viewer.Image)

    ' get the result of image comparison
    Dim imageCompareResult As Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult = recognitionResult.TemplateMatchingResult.ImageCompareResult
    ' if image is recognized
    If imageCompareResult.IsReliable Then
        ' create a visual tool
        Dim formFieldViewerTool As New Vintasoft.Imaging.FormsProcessing.FormRecognition.UI.VisualTools.FormFieldViewerTool()
        ' create a view for the recognized page
        Dim pageView As Vintasoft.Imaging.FormsProcessing.FormRecognition.UI.FormFieldView = Vintasoft.Imaging.FormsProcessing.FormRecognition.UI.FormFieldViewFactory.CreateView(recognitionResult.RecognizedPage)
        ' add the view to the collection of the visual tool
        formFieldViewerTool.FieldViewCollection.Add(pageView)
        ' set the visual tool as current tool of the viewer
        viewer.VisualTool = formFieldViewerTool
        Return True
    Else
        Return False
    End If
End Function

// The project, which uses this code, must have references to the following assemblies:
// - Vintasoft.Imaging
// - Vintasoft.Imaging.FormsProcessing

/// <summary>
/// Recognizes the current image of specified viewer
/// and shows recognition results in viewer.
/// </summary>
/// <param name="viewer">The viewer.</param>
/// <param name="formRecognitionManager">The form recognition manager.</param>
public static bool RecognizeAndShowInViewer(
    Vintasoft.Imaging.UI.ImageViewer viewer,
    Vintasoft.Imaging.FormsProcessing.FormRecognitionManager formRecognitionManager)
{
    // recognize the image
    Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult = 
        formRecognitionManager.Recognize(viewer.Image);

    // get the result of image comparison
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult imageCompareResult =
        recognitionResult.TemplateMatchingResult.ImageCompareResult;
    // if image is recognized
    if (imageCompareResult.IsReliable)
    {
        // create a visual tool
        Vintasoft.Imaging.FormsProcessing.FormRecognition.UI.VisualTools.FormFieldViewerTool formFieldViewerTool = 
            new Vintasoft.Imaging.FormsProcessing.FormRecognition.UI.VisualTools.FormFieldViewerTool();
        // create a view for the recognized page
        Vintasoft.Imaging.FormsProcessing.FormRecognition.UI.FormFieldView pageView = 
            Vintasoft.Imaging.FormsProcessing.FormRecognition.UI.FormFieldViewFactory.CreateView(recognitionResult.RecognizedPage);
        // add the view to the collection of the visual tool
        formFieldViewerTool.FieldViewCollection.Add(pageView);
        // set the visual tool as current tool of the viewer
        viewer.VisualTool = formFieldViewerTool;
        return true;
    }
    else
    {
        return false;
    }
}

Display the recognized filled form on image in WPF image viewer

WpfFormFieldViewerTool class is intended for displaying the recognized filled form on image in WPF image viewer.

Here is an example that demonstrates how to recognize a form and display the results in WPF image viewer.

VB.NET

' The project, which uses this code, must have references to the following assemblies:
' - Vintasoft.Imaging.FormsProcessing
' - Vintasoft.Imaging.FormsProcessing.Wpf.UI
' - Vintasoft.Imaging.Wpf.UI

''' <summary>
''' Recognizes the current image of specified viewer
''' and shows recognition results in viewer.
''' </summary>
''' <param name="viewer">The viewer.</param>
''' <param name="formRecognitionManager">The form recognition manager.</param>
Public Shared Function RecognizeAndShowInViewer(viewer As Vintasoft.Imaging.Wpf.UI.WpfImageViewer, formRecognitionManager As Vintasoft.Imaging.FormsProcessing.FormRecognitionManager) As Boolean
    ' recognize the image
    Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = formRecognitionManager.Recognize(viewer.Image)

    ' get the result of image comparison
    Dim imageCompareResult As Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult = recognitionResult.TemplateMatchingResult.ImageCompareResult
    ' if image is recognized
    If imageCompareResult.IsReliable Then
        ' create a visual tool
        Dim formFieldViewerTool As New Vintasoft.Imaging.FormsProcessing.FormRecognition.Wpf.UI.VisualTools.WpfFormFieldViewerTool()
        ' create a view for the recognized page
        Dim pageView As Vintasoft.Imaging.FormsProcessing.FormRecognition.Wpf.UI.WpfFormFieldView = Vintasoft.Imaging.FormsProcessing.FormRecognition.Wpf.UI.WpfFormFieldViewFactory.CreateView(recognitionResult.RecognizedPage)
        ' add the view to the collection of the visual tool
        formFieldViewerTool.FieldViewCollection.Add(pageView)
        ' set transform matrix and resolution of template image
        formFieldViewerTool.SetTransform(imageCompareResult.TransformMatrix, imageCompareResult.SourceImprint.ImageSize.Resolution)
        ' set the visual tool as current tool of the viewer
        viewer.VisualTool = formFieldViewerTool
        Return True
    Else
        Return False
    End If
End Function

// The project, which uses this code, must have references to the following assemblies:
// - Vintasoft.Imaging.FormsProcessing
// - Vintasoft.Imaging.FormsProcessing.Wpf.UI
// - Vintasoft.Imaging.Wpf.UI

/// <summary>
/// Recognizes the current image of specified viewer
/// and shows recognition results in viewer.
/// </summary>
/// <param name="viewer">The viewer.</param>
/// <param name="formRecognitionManager">The form recognition manager.</param>
public static bool RecognizeAndShowInViewer(
    Vintasoft.Imaging.Wpf.UI.WpfImageViewer viewer,
    Vintasoft.Imaging.FormsProcessing.FormRecognitionManager formRecognitionManager)
{
    // recognize the image
    Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult = 
        formRecognitionManager.Recognize(viewer.Image);

    // get the result of image comparison
    Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult imageCompareResult =
        recognitionResult.TemplateMatchingResult.ImageCompareResult;
    // if image is recognized
    if (imageCompareResult.IsReliable)
    {
        // create a visual tool
        Vintasoft.Imaging.FormsProcessing.FormRecognition.Wpf.UI.VisualTools.WpfFormFieldViewerTool formFieldViewerTool = 
            new Vintasoft.Imaging.FormsProcessing.FormRecognition.Wpf.UI.VisualTools.WpfFormFieldViewerTool();
        // create a view for the recognized page
        Vintasoft.Imaging.FormsProcessing.FormRecognition.Wpf.UI.WpfFormFieldView pageView = 
            Vintasoft.Imaging.FormsProcessing.FormRecognition.Wpf.UI.WpfFormFieldViewFactory.CreateView(recognitionResult.RecognizedPage);
        // add the view to the collection of the visual tool
        formFieldViewerTool.FieldViewCollection.Add(pageView);
        // set transform matrix and resolution of template image
        formFieldViewerTool.SetTransform(
            imageCompareResult.TransformMatrix,
            imageCompareResult.SourceImprint.ImageSize.Resolution);
        // set the visual tool as current tool of the viewer
        viewer.VisualTool = formFieldViewerTool;
        return true;
    }
    else
    {
        return false;
    }
}

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